1. Field of the Invention
The present invention relates to an interconnecting structure for electrically connecting two printed circuit boards leaving a predetermined space therebetween.
2. Related Art
Printed circuit boards each having a plurality of electronic parts attached thereto are used in an electric or electronic apparatus. A single large printed circuit board is divided into a plurality of divisions, which are arranged horizontally at intervals or vertically at different levels to form a horizontal arrangement or vertical stack of divisional printed circuit boards, which are all electrically connected with the aid of connectors.
A variety of connectors are used for connecting divisional printed circuit boards. One example of such connectors is shown in Japanese Patent 11-297387(A), titled “Interconnecting Structure for Electrically Connecting Two Printed Circuit Boards”. It is an improvement of an interconnecting structure for electrically connecting together a first printed circuit board having a female connector part fixed thereto and a second printed circuit board having a male connector part fixed thereto. The female connector part is fixed on the upper side of the first printed circuit board with its receptacle apertures open on the lower side. The male connector part is fixed on the upper side of the second printed circuit board with its terminal pins standing upright. The first printed circuit board is laid above the second printed circuit board with the receptacle apertures of the female connector part aligned with the terminal pins of the male connector part, thus permitting insertion of the terminal pins into the receptacle apertures from the lower side of the first printed circuit board. The feature of the printed circuit board-interconnecting structure resides in that: the male connector part has a cross stopper to determine the space between the first and second printed circuit boards. Specifically, the cross stopper has threaded guide pins standing upright on its opposite ends, and the first printed circuit board has guide holes made therein. The first and second printed circuit boards are combined together by inserting the threaded guide pins in the guide holes, and by fastening them to the first printed circuit board with butterfly nuts.
The male connector part has numerous terminal pins and two threaded guide pins standing upright, passing through the cross stopper. Such a complicated connector part is difficult to produce, and accordingly the manufacturing cost is relatively high. Still disadvantageously the first printed circuit board needs to be laid on the cross stopper with the terminal pins and threaded guide pins of the male connector part inserted in the receptacle apertures and guide holes of the first printed circuit board, and then, the first printed circuit board needs to be fastened to the second printed circuit board by screwing the butterfly nuts onto the threaded guide pins. Thus, assembling work is not easy. Insertion of numerous terminal pins in the through holes made in the cross stopper prevents automatization of the assembling work.
FIG. 7 shows another conventional interconnecting structure, in which first and second printed circuit boards 1 and 2 have female and male connector parts 21 and 22 fixed thereto respectively. The female connector part 21 is ordinary in structure, and less expensive. The male connector part 22, however, is not ordinary, and complicated in structure, and therefore it is much more expensive than the ordinary female connector part.
As is the case the interconnecting structure disclosed in Japan Patent 11-297387(A), the male connector part 22 has numerous terminal pins standing upright to be inserted in the apertures of the female connector part 21, thus preventing automatization of the assembling work. Still disadvantageously, the height of the male connector part varies with the distance between the first and second printed circuit boards 1 and 2. Male connector parts of different heights, therefore, need to be prepared to meet the inter-distance as required.
In view of the above, one object of the present invention is to provide an interconnecting structure which is free of such defects as described above, permitting automatization of the assembling work, enabling two printed circuit boards to be connected together regardless of the board-to-board distance, and reducing the manufacturing cost to the minimum possible.